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Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Accounts Receivable [Member]
Related Party Transaction [Line Items]
Accounts Receivable, Related Parties	$ 0.1
Accounts Payable [Member]
Related Party Transaction [Line Items]
Accounts Payable, Related Parties	2.3
Other Liabilities [Member]
Related Party Transaction [Line Items]
Tax Receivable Agreement, Related Parties	12.9
Allocated Expense [Member] \| Selling, General and Administrative Expenses [Member]
Related Party Transaction [Line Items]
Expenses from Transactions with Related Party		$ 2.3
Separation Costs [Member] \| Selling, General and Administrative Expenses [Member]
Related Party Transaction [Line Items]
Expenses from Transactions with Related Party	1.5	$ 1.2
Master Services Agreement Fees [Member] \| Selling, General and Administrative Expenses [Member]
Related Party Transaction [Line Items]
Expenses from Transactions with Related Party	0.5
Share-based Payment Arrangement [Member] \| Selling, General and Administrative Expenses [Member]
Related Party Transaction [Line Items]
Expenses from Transactions with Related Party	$ 1.1